Combined guide plug and float valve for well casings



Feb. 14, 1928.

L. J. BLACK COMBINED GUIDE PLUG AND FLOAT VALVE FOR WELL CASINGS FiledJuly 19. 1927 Patented Feb. 14, 1928.

UNITED STATES LEE BLACK, or BEAUMONT, TEXAS.

COMBINED GUIDE PLUG AND FLOAT VALVE FOB WELL CASINOS.

Application filed July 19,

This invention relates to a combined guide plug and float valve forwellcasings.

An important object of the invention is to produce a device of thischaracter which may be very readily attached to the casing shoes of thewell casing without in any manner altering the structure thereof, andwhich is capable of use with casing shoes, the internal diameters ofwhich vary between certain limits.

A further object of the invention is to provide a device of thischaracter of such construction that the back pressure valve is locatedabove the upper end of the guide plug and accordingly this guide plugmay be provided with an axial bore which will serve to guide the fluidin a solid stream against an obstacle.

A still further object of the invention is to provide a structure ofthis character, wherein the back pressure valve is so located that itdoes not interfere with the spudding out of bridges formed by cavings inthe bore with the casing.

These and other objects I attain by the construction shown in theaccompanying drawings, wherein for the purpose of illus tration is showna preferred embodiment of my invention and wherein Figure 1 is avertical sectional view of a combined guide plug and float valveconstructed in accordance with my invention;

Figure 2 is a section on the line 2-2 of Figure 1.

Referring now more particularly to the drawings, the numeral 10generally des gnates a casing shoe of a well casing which has its lowerend face downwardly and out wardly tapered, as indicated at 11, n theusual construction of such devices, In accordance with my invention,-Iprovide a hollow plug 12 having a rounded lower end wall 13, which isprovided axially with an opening 14. The plug has an external diameterthe same as that of the casing shoe and has upon its upper end a reducedextension 15, which is connected with the main body of the plug by anoffset, providing an external shoulder 16 having the same taper as thelower face of the casing shoe. The interior of the extension has adownwardly tapering threaded bore 17 and the extension aboye theshoulder 16 is slit at intervals, as indicated at 18. o

A spider 19 is provided, having directed 'theretln'ongh centrally thestem 20 of a valve 1927. Serial No. 206,978.

21, which seats against the lower face of the spider to seal ports 22formed therein against the upward passage'of fluid. The upper end of thestem has a spring seat 23 against which seats one end of a spring 24surrounding the stem and having its lower end abutted against thespider. The outer face of this spider has a taper simi lar to that ofthe bore of the plug extension and is threaded for the coaction of thethreads thereof.

It will be obvious that by seating the plug in the lower end of thecasing shoe and threading the spider thereinto, the upper end of theextension will be expanded and come into tight frictional engagementwith the walls of the casing shoe to connect the plug thereto. It willalso be obvious that since the valve controlling the passage of water islocated well above the upper end of the plug, the fluid passing thisvalve will unite and form a solid stream in passing from the opening 14,so that it will provide an efiicient washing jet for use in settling thepipe. Furthermore, a valve located as described will be free from thedamage ordinarily sustained by such valves during the lowering operationwhere the valve is located at the lower end of the shoe. It will beobvious that the expansion of the upper end of the plug will enable theplug to be adapted to casing shoes wherein the internal diameter variesslightly as, for example, between two casing shoes intended for use withthe same sized casings but with casings having different' weights.

Since the construction hereinbefore set forth is capable of a certainrange of change and modification without materially departing from thespirit of the invention, I do not limit myself to such specificstructure except as hereinafter claimed.

1. In a combined guide plug and float valve for well casings, a hollowuide plug having an axial aperture in its ower end and having at itsupper end an extension adapted for engagement in the bore of a casingshoe. said extension being expansible, a ported spider engagcable insaid upper end to expand the same into clamping engagement with thecasing shoe and a downwardly opening check valve controlling the portsof the spider.

2. In a combined guide plug and float valve for well casings, a guideplug having an axial port-in its lower end and having at its upper endan extension to engage in and substantially fit the bore of a casingshoe,

said extension having a tapered threaded bore, a ported spider having athreaded periphery for engagement in the tapered bore of the extensionand a check valve coacting said extension having a tapered threadedbore, a ported spider having a threaded peri hery for engagement in thetapered bore of the extension and a check valve coacting with the portsof the spider, said extension being slit to permit expansion thereof bysaid spider, the connection of said extension with the pl embodying ashoulder confronting and tting against the lower end of the casing shoe.

4. In a combined guide plug and float valve for well casings, a hollowguide plu having an axial aperture in its lower end and having at itsupper end an extension adapted for engagement in the bore of a easingshoe, said extension being expansible, a ported spider engageable insaid upper end to expand the same into clamping engagement with thecasin shoe and a downwardly opening check va ve-controlling the ports ofthe spider, the connection of said extension with the lug embodying ashoulder confronting and fitting against the lower end of the casingshoe.

5. In a combined guide plug and float valve for well casings, a hollowguide plug having an axial aperture in its lower end and having at itsupper end an extension adaptedto enter the bore of the casing shoe andhaving its walls slotted, the bore of said tubular extension taperingdownwardly and being screw-threaded, a ported spider having a downwardlytapering peripheral wall screw-threaded for engagement with the wall ofthe bore of the extension and an upwardly closing check valvecontrolling the ports of the spider.

6. In a combined guide plug and float valve for well casings, a hollowguide plu having an axial aperture in its lower end and having at itsupper end an extension adapted to enter the bore of the casing shoeandhaving its walls slotted, the bore of said tubular extension taperingdownwardly and being screw-threaded, a ported spider having a downwardlytapering peripheral wall screw-threaded for engagement with the wall ofthe bore of the extension and an upwardly closing check valvecontrolling the ports of the spider, the connection of the reducedextension with the body of the plug providing a shoulder confronting andfitting against the lower end of the casing shoe.

In testimony whereof I afiix my signature.

LEE J. BLACK.

